1 //===-- llvm/Support/Compiler.h - Compiler abstraction support --*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // This file defines several macros, based on the current compiler. This allows 10 // use of compiler-specific features in a way that remains portable. This header 11 // can be included from either C or C++. 12 // 13 //===----------------------------------------------------------------------===// 14 15 #ifndef LLVM_SUPPORT_COMPILER_H 16 #define LLVM_SUPPORT_COMPILER_H 17 18 #include "llvm/Config/llvm-config.h" 19 20 #ifdef __cplusplus 21 #include <new> 22 #endif 23 #include <stddef.h> 24 25 #if defined(_MSC_VER) 26 #include <sal.h> 27 #endif 28 29 #ifndef __has_feature 30 # define __has_feature(x) 0 31 #endif 32 33 #ifndef __has_extension 34 # define __has_extension(x) 0 35 #endif 36 37 #ifndef __has_attribute 38 # define __has_attribute(x) 0 39 #endif 40 41 #ifndef __has_builtin 42 # define __has_builtin(x) 0 43 #endif 44 45 // Only use __has_cpp_attribute in C++ mode. GCC defines __has_cpp_attribute in 46 // C mode, but the :: in __has_cpp_attribute(scoped::attribute) is invalid. 47 #ifndef LLVM_HAS_CPP_ATTRIBUTE 48 #if defined(__cplusplus) && defined(__has_cpp_attribute) 49 # define LLVM_HAS_CPP_ATTRIBUTE(x) __has_cpp_attribute(x) 50 #else 51 # define LLVM_HAS_CPP_ATTRIBUTE(x) 0 52 #endif 53 #endif 54 55 /// \macro LLVM_GNUC_PREREQ 56 /// Extend the default __GNUC_PREREQ even if glibc's features.h isn't 57 /// available. 58 #ifndef LLVM_GNUC_PREREQ 59 # if defined(__GNUC__) && defined(__GNUC_MINOR__) && defined(__GNUC_PATCHLEVEL__) 60 # define LLVM_GNUC_PREREQ(maj, min, patch) \ 61 ((__GNUC__ << 20) + (__GNUC_MINOR__ << 10) + __GNUC_PATCHLEVEL__ >= \ 62 ((maj) << 20) + ((min) << 10) + (patch)) 63 # elif defined(__GNUC__) && defined(__GNUC_MINOR__) 64 # define LLVM_GNUC_PREREQ(maj, min, patch) \ 65 ((__GNUC__ << 20) + (__GNUC_MINOR__ << 10) >= ((maj) << 20) + ((min) << 10)) 66 # else 67 # define LLVM_GNUC_PREREQ(maj, min, patch) 0 68 # endif 69 #endif 70 71 /// \macro LLVM_MSC_PREREQ 72 /// Is the compiler MSVC of at least the specified version? 73 /// The common \param version values to check for are: 74 /// * 1910: VS2017, version 15.1 & 15.2 75 /// * 1911: VS2017, version 15.3 & 15.4 76 /// * 1912: VS2017, version 15.5 77 /// * 1913: VS2017, version 15.6 78 /// * 1914: VS2017, version 15.7 79 /// * 1915: VS2017, version 15.8 80 /// * 1916: VS2017, version 15.9 81 /// * 1920: VS2019, version 16.0 82 /// * 1921: VS2019, version 16.1 83 #ifdef _MSC_VER 84 #define LLVM_MSC_PREREQ(version) (_MSC_VER >= (version)) 85 86 // We require at least MSVC 2017. 87 #if !LLVM_MSC_PREREQ(1910) 88 #error LLVM requires at least MSVC 2017. 89 #endif 90 91 #else 92 #define LLVM_MSC_PREREQ(version) 0 93 #endif 94 95 /// Does the compiler support ref-qualifiers for *this? 96 /// 97 /// Sadly, this is separate from just rvalue reference support because GCC 98 /// and MSVC implemented this later than everything else. This appears to be 99 /// corrected in MSVC 2019 but not MSVC 2017. 100 #if __has_feature(cxx_rvalue_references) || LLVM_GNUC_PREREQ(4, 8, 1) 101 #define LLVM_HAS_RVALUE_REFERENCE_THIS 1 102 #else 103 #define LLVM_HAS_RVALUE_REFERENCE_THIS 0 104 #endif 105 106 /// Expands to '&' if ref-qualifiers for *this are supported. 107 /// 108 /// This can be used to provide lvalue/rvalue overrides of member functions. 109 /// The rvalue override should be guarded by LLVM_HAS_RVALUE_REFERENCE_THIS 110 #if LLVM_HAS_RVALUE_REFERENCE_THIS 111 #define LLVM_LVALUE_FUNCTION & 112 #else 113 #define LLVM_LVALUE_FUNCTION 114 #endif 115 116 /// LLVM_LIBRARY_VISIBILITY - If a class marked with this attribute is linked 117 /// into a shared library, then the class should be private to the library and 118 /// not accessible from outside it. Can also be used to mark variables and 119 /// functions, making them private to any shared library they are linked into. 120 /// On PE/COFF targets, library visibility is the default, so this isn't needed. 121 /// 122 /// LLVM_EXTERNAL_VISIBILITY - classes, functions, and variables marked with 123 /// this attribute will be made public and visible outside of any shared library 124 /// they are linked in to. 125 #if (__has_attribute(visibility) || LLVM_GNUC_PREREQ(4, 0, 0)) && \ 126 !defined(__MINGW32__) && !defined(__CYGWIN__) && !defined(_WIN32) 127 #define LLVM_LIBRARY_VISIBILITY __attribute__ ((visibility("hidden"))) 128 #define LLVM_EXTERNAL_VISIBILITY __attribute__ ((visibility("default"))) 129 #else 130 #define LLVM_LIBRARY_VISIBILITY 131 #define LLVM_EXTERNAL_VISIBILITY 132 #endif 133 134 #if defined(__GNUC__) 135 #define LLVM_PREFETCH(addr, rw, locality) __builtin_prefetch(addr, rw, locality) 136 #else 137 #define LLVM_PREFETCH(addr, rw, locality) 138 #endif 139 140 #if __has_attribute(used) || LLVM_GNUC_PREREQ(3, 1, 0) 141 #define LLVM_ATTRIBUTE_USED __attribute__((__used__)) 142 #else 143 #define LLVM_ATTRIBUTE_USED 144 #endif 145 146 /// LLVM_NODISCARD - Warn if a type or return value is discarded. 147 148 // Use the 'nodiscard' attribute in C++17 or newer mode. 149 #if __cplusplus > 201402L && LLVM_HAS_CPP_ATTRIBUTE(nodiscard) 150 #define LLVM_NODISCARD [[nodiscard]] 151 #elif LLVM_HAS_CPP_ATTRIBUTE(clang::warn_unused_result) 152 #define LLVM_NODISCARD [[clang::warn_unused_result]] 153 // Clang in C++14 mode claims that it has the 'nodiscard' attribute, but also 154 // warns in the pedantic mode that 'nodiscard' is a C++17 extension (PR33518). 155 // Use the 'nodiscard' attribute in C++14 mode only with GCC. 156 // TODO: remove this workaround when PR33518 is resolved. 157 #elif defined(__GNUC__) && LLVM_HAS_CPP_ATTRIBUTE(nodiscard) 158 #define LLVM_NODISCARD [[nodiscard]] 159 #else 160 #define LLVM_NODISCARD 161 #endif 162 163 // Indicate that a non-static, non-const C++ member function reinitializes 164 // the entire object to a known state, independent of the previous state of 165 // the object. 166 // 167 // The clang-tidy check bugprone-use-after-move recognizes this attribute as a 168 // marker that a moved-from object has left the indeterminate state and can be 169 // reused. 170 #if LLVM_HAS_CPP_ATTRIBUTE(clang::reinitializes) 171 #define LLVM_ATTRIBUTE_REINITIALIZES [[clang::reinitializes]] 172 #else 173 #define LLVM_ATTRIBUTE_REINITIALIZES 174 #endif 175 176 // Some compilers warn about unused functions. When a function is sometimes 177 // used or not depending on build settings (e.g. a function only called from 178 // within "assert"), this attribute can be used to suppress such warnings. 179 // 180 // However, it shouldn't be used for unused *variables*, as those have a much 181 // more portable solution: 182 // (void)unused_var_name; 183 // Prefer cast-to-void wherever it is sufficient. 184 #if __has_attribute(unused) || LLVM_GNUC_PREREQ(3, 1, 0) 185 #define LLVM_ATTRIBUTE_UNUSED __attribute__((__unused__)) 186 #else 187 #define LLVM_ATTRIBUTE_UNUSED 188 #endif 189 190 // FIXME: Provide this for PE/COFF targets. 191 #if (__has_attribute(weak) || LLVM_GNUC_PREREQ(4, 0, 0)) && \ 192 (!defined(__MINGW32__) && !defined(__CYGWIN__) && !defined(_WIN32)) 193 #define LLVM_ATTRIBUTE_WEAK __attribute__((__weak__)) 194 #else 195 #define LLVM_ATTRIBUTE_WEAK 196 #endif 197 198 // Prior to clang 3.2, clang did not accept any spelling of 199 // __has_attribute(const), so assume it is supported. 200 #if defined(__clang__) || defined(__GNUC__) 201 // aka 'CONST' but following LLVM Conventions. 202 #define LLVM_READNONE __attribute__((__const__)) 203 #else 204 #define LLVM_READNONE 205 #endif 206 207 #if __has_attribute(pure) || defined(__GNUC__) 208 // aka 'PURE' but following LLVM Conventions. 209 #define LLVM_READONLY __attribute__((__pure__)) 210 #else 211 #define LLVM_READONLY 212 #endif 213 214 #if __has_builtin(__builtin_expect) || LLVM_GNUC_PREREQ(4, 0, 0) 215 #define LLVM_LIKELY(EXPR) __builtin_expect((bool)(EXPR), true) 216 #define LLVM_UNLIKELY(EXPR) __builtin_expect((bool)(EXPR), false) 217 #else 218 #define LLVM_LIKELY(EXPR) (EXPR) 219 #define LLVM_UNLIKELY(EXPR) (EXPR) 220 #endif 221 222 /// LLVM_ATTRIBUTE_NOINLINE - On compilers where we have a directive to do so, 223 /// mark a method "not for inlining". 224 #if __has_attribute(noinline) || LLVM_GNUC_PREREQ(3, 4, 0) 225 #define LLVM_ATTRIBUTE_NOINLINE __attribute__((noinline)) 226 #elif defined(_MSC_VER) 227 #define LLVM_ATTRIBUTE_NOINLINE __declspec(noinline) 228 #else 229 #define LLVM_ATTRIBUTE_NOINLINE 230 #endif 231 232 /// LLVM_ATTRIBUTE_ALWAYS_INLINE - On compilers where we have a directive to do 233 /// so, mark a method "always inline" because it is performance sensitive. GCC 234 /// 3.4 supported this but is buggy in various cases and produces unimplemented 235 /// errors, just use it in GCC 4.0 and later. 236 #if __has_attribute(always_inline) || LLVM_GNUC_PREREQ(4, 0, 0) 237 #define LLVM_ATTRIBUTE_ALWAYS_INLINE __attribute__((always_inline)) 238 #elif defined(_MSC_VER) 239 #define LLVM_ATTRIBUTE_ALWAYS_INLINE __forceinline 240 #else 241 #define LLVM_ATTRIBUTE_ALWAYS_INLINE 242 #endif 243 244 #ifdef __GNUC__ 245 #define LLVM_ATTRIBUTE_NORETURN __attribute__((noreturn)) 246 #elif defined(_MSC_VER) 247 #define LLVM_ATTRIBUTE_NORETURN __declspec(noreturn) 248 #else 249 #define LLVM_ATTRIBUTE_NORETURN 250 #endif 251 252 #if __has_attribute(returns_nonnull) || LLVM_GNUC_PREREQ(4, 9, 0) 253 #define LLVM_ATTRIBUTE_RETURNS_NONNULL __attribute__((returns_nonnull)) 254 #elif defined(_MSC_VER) 255 #define LLVM_ATTRIBUTE_RETURNS_NONNULL _Ret_notnull_ 256 #else 257 #define LLVM_ATTRIBUTE_RETURNS_NONNULL 258 #endif 259 260 /// \macro LLVM_ATTRIBUTE_RETURNS_NOALIAS Used to mark a function as returning a 261 /// pointer that does not alias any other valid pointer. 262 #ifdef __GNUC__ 263 #define LLVM_ATTRIBUTE_RETURNS_NOALIAS __attribute__((__malloc__)) 264 #elif defined(_MSC_VER) 265 #define LLVM_ATTRIBUTE_RETURNS_NOALIAS __declspec(restrict) 266 #else 267 #define LLVM_ATTRIBUTE_RETURNS_NOALIAS 268 #endif 269 270 /// LLVM_FALLTHROUGH - Mark fallthrough cases in switch statements. 271 #if __cplusplus > 201402L && LLVM_HAS_CPP_ATTRIBUTE(fallthrough) 272 #define LLVM_FALLTHROUGH [[fallthrough]] 273 #elif LLVM_HAS_CPP_ATTRIBUTE(gnu::fallthrough) 274 #define LLVM_FALLTHROUGH [[gnu::fallthrough]] 275 #elif __has_attribute(fallthrough) 276 #define LLVM_FALLTHROUGH __attribute__((fallthrough)) 277 #elif LLVM_HAS_CPP_ATTRIBUTE(clang::fallthrough) 278 #define LLVM_FALLTHROUGH [[clang::fallthrough]] 279 #else 280 #define LLVM_FALLTHROUGH 281 #endif 282 283 /// LLVM_REQUIRE_CONSTANT_INITIALIZATION - Apply this to globals to ensure that 284 /// they are constant initialized. 285 #if LLVM_HAS_CPP_ATTRIBUTE(clang::require_constant_initialization) 286 #define LLVM_REQUIRE_CONSTANT_INITIALIZATION \ 287 [[clang::require_constant_initialization]] 288 #else 289 #define LLVM_REQUIRE_CONSTANT_INITIALIZATION 290 #endif 291 292 /// LLVM_GSL_OWNER - Apply this to owning classes like SmallVector to enable 293 /// lifetime warnings. 294 #if LLVM_HAS_CPP_ATTRIBUTE(gsl::Owner) 295 #define LLVM_GSL_OWNER [[gsl::Owner]] 296 #else 297 #define LLVM_GSL_OWNER 298 #endif 299 300 /// LLVM_GSL_POINTER - Apply this to non-owning classes like 301 /// StringRef to enable lifetime warnings. 302 #if LLVM_HAS_CPP_ATTRIBUTE(gsl::Pointer) 303 #define LLVM_GSL_POINTER [[gsl::Pointer]] 304 #else 305 #define LLVM_GSL_POINTER 306 #endif 307 308 /// LLVM_EXTENSION - Support compilers where we have a keyword to suppress 309 /// pedantic diagnostics. 310 #ifdef __GNUC__ 311 #define LLVM_EXTENSION __extension__ 312 #else 313 #define LLVM_EXTENSION 314 #endif 315 316 // LLVM_ATTRIBUTE_DEPRECATED(decl, "message") 317 #if __has_feature(attribute_deprecated_with_message) 318 # define LLVM_ATTRIBUTE_DEPRECATED(decl, message) \ 319 decl __attribute__((deprecated(message))) 320 #elif defined(__GNUC__) 321 # define LLVM_ATTRIBUTE_DEPRECATED(decl, message) \ 322 decl __attribute__((deprecated)) 323 #elif defined(_MSC_VER) 324 # define LLVM_ATTRIBUTE_DEPRECATED(decl, message) \ 325 __declspec(deprecated(message)) decl 326 #else 327 # define LLVM_ATTRIBUTE_DEPRECATED(decl, message) \ 328 decl 329 #endif 330 331 /// LLVM_BUILTIN_UNREACHABLE - On compilers which support it, expands 332 /// to an expression which states that it is undefined behavior for the 333 /// compiler to reach this point. Otherwise is not defined. 334 #if __has_builtin(__builtin_unreachable) || LLVM_GNUC_PREREQ(4, 5, 0) 335 # define LLVM_BUILTIN_UNREACHABLE __builtin_unreachable() 336 #elif defined(_MSC_VER) 337 # define LLVM_BUILTIN_UNREACHABLE __assume(false) 338 #endif 339 340 /// LLVM_BUILTIN_TRAP - On compilers which support it, expands to an expression 341 /// which causes the program to exit abnormally. 342 #if __has_builtin(__builtin_trap) || LLVM_GNUC_PREREQ(4, 3, 0) 343 # define LLVM_BUILTIN_TRAP __builtin_trap() 344 #elif defined(_MSC_VER) 345 // The __debugbreak intrinsic is supported by MSVC, does not require forward 346 // declarations involving platform-specific typedefs (unlike RaiseException), 347 // results in a call to vectored exception handlers, and encodes to a short 348 // instruction that still causes the trapping behavior we want. 349 # define LLVM_BUILTIN_TRAP __debugbreak() 350 #else 351 # define LLVM_BUILTIN_TRAP *(volatile int*)0x11 = 0 352 #endif 353 354 /// LLVM_BUILTIN_DEBUGTRAP - On compilers which support it, expands to 355 /// an expression which causes the program to break while running 356 /// under a debugger. 357 #if __has_builtin(__builtin_debugtrap) 358 # define LLVM_BUILTIN_DEBUGTRAP __builtin_debugtrap() 359 #elif defined(_MSC_VER) 360 // The __debugbreak intrinsic is supported by MSVC and breaks while 361 // running under the debugger, and also supports invoking a debugger 362 // when the OS is configured appropriately. 363 # define LLVM_BUILTIN_DEBUGTRAP __debugbreak() 364 #else 365 // Just continue execution when built with compilers that have no 366 // support. This is a debugging aid and not intended to force the 367 // program to abort if encountered. 368 # define LLVM_BUILTIN_DEBUGTRAP 369 #endif 370 371 /// \macro LLVM_ASSUME_ALIGNED 372 /// Returns a pointer with an assumed alignment. 373 #if __has_builtin(__builtin_assume_aligned) || LLVM_GNUC_PREREQ(4, 7, 0) 374 # define LLVM_ASSUME_ALIGNED(p, a) __builtin_assume_aligned(p, a) 375 #elif defined(LLVM_BUILTIN_UNREACHABLE) 376 # define LLVM_ASSUME_ALIGNED(p, a) \ 377 (((uintptr_t(p) % (a)) == 0) ? (p) : (LLVM_BUILTIN_UNREACHABLE, (p))) 378 #else 379 # define LLVM_ASSUME_ALIGNED(p, a) (p) 380 #endif 381 382 /// \macro LLVM_PACKED 383 /// Used to specify a packed structure. 384 /// LLVM_PACKED( 385 /// struct A { 386 /// int i; 387 /// int j; 388 /// int k; 389 /// long long l; 390 /// }); 391 /// 392 /// LLVM_PACKED_START 393 /// struct B { 394 /// int i; 395 /// int j; 396 /// int k; 397 /// long long l; 398 /// }; 399 /// LLVM_PACKED_END 400 #ifdef _MSC_VER 401 # define LLVM_PACKED(d) __pragma(pack(push, 1)) d __pragma(pack(pop)) 402 # define LLVM_PACKED_START __pragma(pack(push, 1)) 403 # define LLVM_PACKED_END __pragma(pack(pop)) 404 #else 405 # define LLVM_PACKED(d) d __attribute__((packed)) 406 # define LLVM_PACKED_START _Pragma("pack(push, 1)") 407 # define LLVM_PACKED_END _Pragma("pack(pop)") 408 #endif 409 410 /// \macro LLVM_PTR_SIZE 411 /// A constant integer equivalent to the value of sizeof(void*). 412 /// Generally used in combination with alignas or when doing computation in the 413 /// preprocessor. 414 #ifdef __SIZEOF_POINTER__ 415 # define LLVM_PTR_SIZE __SIZEOF_POINTER__ 416 #elif defined(_WIN64) 417 # define LLVM_PTR_SIZE 8 418 #elif defined(_WIN32) 419 # define LLVM_PTR_SIZE 4 420 #elif defined(_MSC_VER) 421 # error "could not determine LLVM_PTR_SIZE as a constant int for MSVC" 422 #else 423 # define LLVM_PTR_SIZE sizeof(void *) 424 #endif 425 426 /// \macro LLVM_MEMORY_SANITIZER_BUILD 427 /// Whether LLVM itself is built with MemorySanitizer instrumentation. 428 #if __has_feature(memory_sanitizer) 429 # define LLVM_MEMORY_SANITIZER_BUILD 1 430 # include <sanitizer/msan_interface.h> 431 # define LLVM_NO_SANITIZE_MEMORY_ATTRIBUTE __attribute__((no_sanitize_memory)) 432 #else 433 # define LLVM_MEMORY_SANITIZER_BUILD 0 434 # define __msan_allocated_memory(p, size) 435 # define __msan_unpoison(p, size) 436 # define LLVM_NO_SANITIZE_MEMORY_ATTRIBUTE 437 #endif 438 439 /// \macro LLVM_ADDRESS_SANITIZER_BUILD 440 /// Whether LLVM itself is built with AddressSanitizer instrumentation. 441 #if __has_feature(address_sanitizer) || defined(__SANITIZE_ADDRESS__) 442 # define LLVM_ADDRESS_SANITIZER_BUILD 1 443 # include <sanitizer/asan_interface.h> 444 #else 445 # define LLVM_ADDRESS_SANITIZER_BUILD 0 446 # define __asan_poison_memory_region(p, size) 447 # define __asan_unpoison_memory_region(p, size) 448 #endif 449 450 /// \macro LLVM_THREAD_SANITIZER_BUILD 451 /// Whether LLVM itself is built with ThreadSanitizer instrumentation. 452 #if __has_feature(thread_sanitizer) || defined(__SANITIZE_THREAD__) 453 # define LLVM_THREAD_SANITIZER_BUILD 1 454 #else 455 # define LLVM_THREAD_SANITIZER_BUILD 0 456 #endif 457 458 #if LLVM_THREAD_SANITIZER_BUILD 459 // Thread Sanitizer is a tool that finds races in code. 460 // See http://code.google.com/p/data-race-test/wiki/DynamicAnnotations . 461 // tsan detects these exact functions by name. 462 #ifdef __cplusplus 463 extern "C" { 464 #endif 465 void AnnotateHappensAfter(const char *file, int line, const volatile void *cv); 466 void AnnotateHappensBefore(const char *file, int line, const volatile void *cv); 467 void AnnotateIgnoreWritesBegin(const char *file, int line); 468 void AnnotateIgnoreWritesEnd(const char *file, int line); 469 #ifdef __cplusplus 470 } 471 #endif 472 473 // This marker is used to define a happens-before arc. The race detector will 474 // infer an arc from the begin to the end when they share the same pointer 475 // argument. 476 # define TsanHappensBefore(cv) AnnotateHappensBefore(__FILE__, __LINE__, cv) 477 478 // This marker defines the destination of a happens-before arc. 479 # define TsanHappensAfter(cv) AnnotateHappensAfter(__FILE__, __LINE__, cv) 480 481 // Ignore any races on writes between here and the next TsanIgnoreWritesEnd. 482 # define TsanIgnoreWritesBegin() AnnotateIgnoreWritesBegin(__FILE__, __LINE__) 483 484 // Resume checking for racy writes. 485 # define TsanIgnoreWritesEnd() AnnotateIgnoreWritesEnd(__FILE__, __LINE__) 486 #else 487 # define TsanHappensBefore(cv) 488 # define TsanHappensAfter(cv) 489 # define TsanIgnoreWritesBegin() 490 # define TsanIgnoreWritesEnd() 491 #endif 492 493 /// \macro LLVM_NO_SANITIZE 494 /// Disable a particular sanitizer for a function. 495 #if __has_attribute(no_sanitize) 496 #define LLVM_NO_SANITIZE(KIND) __attribute__((no_sanitize(KIND))) 497 #else 498 #define LLVM_NO_SANITIZE(KIND) 499 #endif 500 501 /// Mark debug helper function definitions like dump() that should not be 502 /// stripped from debug builds. 503 /// Note that you should also surround dump() functions with 504 /// `#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)` so they do always 505 /// get stripped in release builds. 506 // FIXME: Move this to a private config.h as it's not usable in public headers. 507 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) 508 #define LLVM_DUMP_METHOD LLVM_ATTRIBUTE_NOINLINE LLVM_ATTRIBUTE_USED 509 #else 510 #define LLVM_DUMP_METHOD LLVM_ATTRIBUTE_NOINLINE 511 #endif 512 513 /// \macro LLVM_PRETTY_FUNCTION 514 /// Gets a user-friendly looking function signature for the current scope 515 /// using the best available method on each platform. The exact format of the 516 /// resulting string is implementation specific and non-portable, so this should 517 /// only be used, for example, for logging or diagnostics. 518 #if defined(_MSC_VER) 519 #define LLVM_PRETTY_FUNCTION __FUNCSIG__ 520 #elif defined(__GNUC__) || defined(__clang__) 521 #define LLVM_PRETTY_FUNCTION __PRETTY_FUNCTION__ 522 #else 523 #define LLVM_PRETTY_FUNCTION __func__ 524 #endif 525 526 /// \macro LLVM_THREAD_LOCAL 527 /// A thread-local storage specifier which can be used with globals, 528 /// extern globals, and static globals. 529 /// 530 /// This is essentially an extremely restricted analog to C++11's thread_local 531 /// support. It uses thread_local if available, falling back on gcc __thread 532 /// if not. __thread doesn't support many of the C++11 thread_local's 533 /// features. You should only use this for PODs that you can statically 534 /// initialize to some constant value. In almost all circumstances this is most 535 /// appropriate for use with a pointer, integer, or small aggregation of 536 /// pointers and integers. 537 #if LLVM_ENABLE_THREADS 538 #if __has_feature(cxx_thread_local) || defined(_MSC_VER) 539 #define LLVM_THREAD_LOCAL thread_local 540 #else 541 // Clang, GCC, and other compatible compilers used __thread prior to C++11 and 542 // we only need the restricted functionality that provides. 543 #define LLVM_THREAD_LOCAL __thread 544 #endif 545 #else // !LLVM_ENABLE_THREADS 546 // If threading is disabled entirely, this compiles to nothing and you get 547 // a normal global variable. 548 #define LLVM_THREAD_LOCAL 549 #endif 550 551 /// \macro LLVM_ENABLE_EXCEPTIONS 552 /// Whether LLVM is built with exception support. 553 #if __has_feature(cxx_exceptions) 554 #define LLVM_ENABLE_EXCEPTIONS 1 555 #elif defined(__GNUC__) && defined(__EXCEPTIONS) 556 #define LLVM_ENABLE_EXCEPTIONS 1 557 #elif defined(_MSC_VER) && defined(_CPPUNWIND) 558 #define LLVM_ENABLE_EXCEPTIONS 1 559 #endif 560 561 #endif 562